Selective ground flood around reduced land pad on package base layer to enable high speed land grid array (lga) socket

ABSTRACT

Embodiments include a transmission line-land grid array (TL-LGA) socket assembly, a TL-LGA socket, and a package substrate. The TL-LGA socket assembly includes a TL-LGA socket having an interconnect in a housing body, the interconnect includes a vertical portion and a horizontal portion. The housing body has a top surface and a bottom surface, where the top surface is a conductive layer. The TL-LGA socket assembly also includes a package substrate having a base layer having a signal pad and a ground strip. The base layer is above the conductive layer of the housing body of the TL-LGA socket. The ground strip is above the horizontal portion of the interconnect and adjacent to the signal pad. The horizontal portion is coupled to the signal pad on the base layer. The package substrate may have a pad with a reduced pad area.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/938,980, filed on Mar. 28, 2018, the entire contents of which ishereby incorporated by reference herein.

FIELD

Embodiments relate to packaging semiconductor devices. Moreparticularly, the embodiments relate to an electrical connector, such asa high-speed land grid array (LGA) socket with a selective ground floodstrip adjacent to a reduced land pad on a base layer.

BACKGROUND

Various types of conventional electrical connectors are known forelectrically connecting an integrated circuit (IC) package, such as acentral process unit (CPU), with a printed circuit board (PCB). One ofthe electrical connectors typically used is an land grid array (LGA)socket, which is particularly utilized for electrically connecting ICpackages/devices with circuit boards. The LGA socket is a type ofsurface-mount packaging socket connector for ICs that use pins on thesocket to connect, for example, the CPU to the PCB. Typically, an LGAsocket has a grid of spring-like contacts, each with a landing pad forengagement with a respective metallic pad on the underside of a packagedelectronic device.

These LGA sockets generally have lands or pads which are placed on1.0-mm centerline spacing and below. These LGA sockets are profiled witharrays of 50 by 50 and even greater. Given the plurality of lands andcontacts, their centerline spacing, and given the design rules for thevertical and horizontal portions of each contact, the LGA sockets causea variety of problems in practice in connection with the electricalperformance, costs, life span, and scaliability of these LGA sockets.

One of these problems is a heightened insertion loss as the LGA socketis used to connect high volume CPU sockets. The LGA socket also posesextremely challenging channel electrical budgets at higher frequencies.In addition, these LGA sockets are typically limited with data ratedemands and scalability. Another problem is the size of the LGA land padareas which are typically larger than what is required. Furthermore,other alternative electrical connectors currently used are pogo-pin testsockets. The pogo-pin test sockets facilitate with some of theincreasing electrical demands needed in the existing sockettechnologies, however the pogo-pin test sockets emanate an exceedinglyhigh cost compared to the LGA sockets.

As successive generations of integrated circuit fabrication continue toscale in size and speed, the electrical sockets used to connect ICpackages will have to accommodate stricter electrical performances suchas lower impedance mismatch, reduced return loss and insertion loss overa broader frequency, higher speed data rates, and/or the like.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments described herein illustrated by way of example and notlimitation in the figures of the accompanying drawings, in which likereferences indicate similar features. Furthermore, some conventionaldetails have been omitted so as not to obscure from the inventiveconcepts described herein.

FIG. 1 is a cross-section view of a transmission line of a land gridarray (LGA) (TL-LGA) socket having a vertical portion, a horizontalportion, and a solder ball, according to one embodiment.

FIG. 2A is a top, perspective view of a coaxial cable having a pluralityof TL-LGA vertical portions with a signal pin and ground pins, accordingto embodiment. FIG. 2B is a top, perspective view of a coaxial cablehaving a plurality of inter-stitched plated-through holes (PTHs) and aplurality of TL-LGA vertical portions with signal pins, according toembodiment.

FIG. 3A is a top, perspective view of a TL-LGA socket including aninterconnect with a horizontal portion coupled to a pad of a base layerof a package, according to one embodiment. FIG. 3B is a cross-sectionalview of a TL-LGA socket including an interconnect with a horizontalportion coupled to a pad of a base layer of a package, according to oneembodiment.

FIG. 4 is a top, perspective view of a plurality of interconnects of aTL-LGA socket, according to one embodiment.

FIG. 5A is a top, perspective view of an interconnect of a TL-LGA sockethaving a vertical portion and a horizontal portion, according to oneembodiment. FIG. 5B is a cross-sectional view of an interconnect of aTL-LGA socket having a vertical portion and a horizontal portion,according to one embodiment.

FIG. 6A is a plan view of a package with a base layer that includes aflooded ground plane, a plurality of pads, and a plurality of padopenings, and a TL-LGA socket including a plurality of TL-LGAinterconnects with horizontal portions, according to embodiment. FIG. 6Bis a plan view of a package with a base layer that includes a floodedground plane, a plurality of pads, and a plurality of pad openings,according to embodiment.

FIG. 7A is a plan view of a package with a base layer that includes aplurality of ground strips and a plurality of pads, and a TL-LGA socketincluding a plurality of TL-LGA interconnects with horizontal portions,according to embodiment. FIG. 7B is a plan view of a package with a baselayer that includes a plurality of ground strips and a plurality ofpads, according to embodiment.

FIG. 8 is a cross-sectional view of an assembly having an integratedcircuit die, a package substrate with a base layer, a TL-LGA socket, anda substrate, according to one embodiment.

FIG. 9 is a schematic block diagram illustrating a computer system thatutilizes a device package having a TL-LGA socket assembly, according toone embodiment.

DETAILED DESCRIPTION

Embodiments described herein variously include techniques or devices forenabling a high-speed land grid array (LGA) socket, such as atransmission line (TL)-LGA (hereinafter, referred to as “TL-LGA”)socket, having interconnects that are positioned below selectivelygrounded strips that are adjacent to reduced LGA land pads on a baselayer of a package. Specifically, embodiments described herein alsoinclude the TL-LGA socket having cascaded transmission line (orinterconnect) structures for facilitating maximum bandwidth and datarate speeds. Various embodiments exploit mechanisms for providing TL-LGAsocket connector structures that can be coupled to LGA land pads withreduced pad sizes that are positioned adjacent to selective groundstrips on the package, where these TL-LGA socket connector structuresfacilitate high-speed signaling pins of the TL-LGA socket.

These embodiments help to improve the LGA technologies and designs byapproximating each critical portion of the socket pin (also referred toas a TL-LGA interconnect) with transmission line structures and designrules (e.g., the TL-LGA interconnects are arranged in a cascadingpattern as shown in FIG. 4). Accordingly, the embodiments describedherein pattern the TL-LGA interconnects in a cascadedconfiguration/design within the TL-LGA socket to enable (i) a reducedimpedance mismatch, and (ii) a lowered/optimized return loss andinsertion loss performance over a broad frequency spectrum to supporthigh-speed data rate demands.

As used herein, a “transmission line” (also referred to as aninterconnect, a transmission line LGA, a TL-LGA interconnect, a TL-LGAsocket interconnect, a LGA contact/pin, etc.) refers to an interconnect(or a socket pin/contact) of a TL-LGA socket that includes a verticalportion and a cantilever (a horizontal portion) that is coupled to a padof a package (e.g., as shown in FIG. 1). Additionally, one or more“transmission lines” may be formed (or redesigned) to have a coaxialcable transmission line design/structure (e.g., as shown in FIGS. 2A-2B)in a housing body of the TL-LGA socket (i.e., the vertical portions ofthe “transmission lines” form the coaxial cable). As used herein, a“coaxial cable” design refers to a shape/pattern that includes an inner(or center) conductor (e.g., a signal socket pin/pad) surrounded by anouter conductor, which may include one or more grounded contacts (orpads/vertical portions) and/or one or more grounded inter-stitchedplated-through holes (PTHs). Note that a grounded component (e.g., agrounded pad) may be a pad that is coupled to a ground reference (or aground plate, a grounded reference point, etc.).

According to some embodiments, a TL-LGA socket and a TL-LGA socketassembly are described. For one embodiment, the TL-LGA socket assembly(e.g., as shown in FIG. 8) includes a TL-LGA socket having aninterconnect disposed in a housing body (e.g., as shown in FIGS. 4 and5A-5B). The interconnect may have a vertical portion and a horizontalportion (also referred to as a cantilever) (e.g., as shown in FIGS. 1,3A-3B, 4, 5A-5B, and 6A-7A). The housing body may include a top surfaceand a bottom surface that is opposite from the top surface (e.g., asshown in FIGS. 4 and 5A-5B), where the top surface may be a conductivelayer. For another embodiment, the TL-LGA socket assembly furtherincludes a package having a base layer, where the base layer includes asignal pad and a ground strip (e.g., as shown in FIGS. 6A-6B-7A-7B). Thebase layer of the package may be disposed above the conductive layer ofthe housing body of the TL-LGA socket (e.g., as shown in FIGS. 3A-3B and6A-7A). For one embodiment, the horizontal portion of the interconnectof the TL-LGA socket is coupled to the signal pad on the base layer ofthe package (e.g., as shown in FIGS. 3A-3B and 6A-7A). For oneembodiment, the ground strip may be disposed above the horizontalportion of the interconnect of the TL-LGA socket and may be adjacent tothe signal pad on the base layer, according to one embodiment (e.g., asshown in FIG. 7A). For one embodiment, the horizontal portion of theinterconnect of the TL-LGA socket is coupled to the signal pad on thebase layer (e.g., as shown in FIGS. 3A-3B, 6A, 7A, and 8).

As used herein, a “TL-LGA socket assembly” refers to a packagingassembly that includes at least a TL-LGA socket and/or a package asdescribed herein, where the package may be coupled to the TL-LGA socket.According to some embodiments, a TL-LGA socket is described. For oneembodiment, the TL-LGA socket has a plurality of interconnects, where aninterconnect includes a vertical portion and a horizontal portion (alsoreferred to as a cantilever) (e.g., as shown in FIGS. 1 and 5A-5B). Forone embodiment, the TL-LGA socket also includes a housing body that hasa top surface and a bottom surface that is opposite from the top surface(e.g., as shown in FIGS. 4 and 5A-5B). The housing body may have thevertical portions of the plurality of interconnects disposed in thehousing body, where the plurality of interconnects are disposed in thehousing body to form a plurality of cascaded transmission lines (e.g.,as shown in FIG. 4). For example, the vertical portions of the TL-LGAinterconnects are disposed in the housing body, and the TL-LGAinterconnects may be arranged (or positioned) in a cascadedconfiguration—i.e., a first TL-LGA interconnect is disposed on a firstposition of a first row, a second TL-LGA interconnect is disposed on asecond position of a second row, and so on—to form a plurality ofcascaded transmission lines in the house body.

As used herein, a “cascaded configuration” may refer to a zig-zag lineof components in a vertical direction. For example, cascadedinterconnects (or cascaded transmission lines) may refer to TL-LGAinterconnects arranged/positioned in the TL-LGA socket in a zig-zag linein a vertical direction (e.g., as shown in FIG. 4). Furthermore, theembodiments of the TL-LGA socket dispose a plurality of transmissionlines in a housing body to form cascaded transmission lines (or acascaded interconnect structures) that improves the bandwidth and datarate speeds of the TL-LGA socket. As used herein, “cascaded transmissionlines” refer to two or more TL-LGA transmission lines (or interconnects)arranged in a cascaded configuration (or a cascading pattern) (e.g., asshown in FIG. 4), where a sequence (or stream) of transmission lines arepositioned and follow as falling like a cascade (i.e., a first TL-LGAtransmission line is disposed on a first position of a first row, asecond TL-LGA transmission line is disposed on a second position of asecond row, and so on, to form a plurality of cascaded transmissionlines). As such, the cascaded transmission lines are formed in theTL-LGA socket by positioning the interconnects in zig-zag lines in thevertical direction.

For additional embodiments, the TL-LGA socket further includes a packagehaving a base layer as the base layer includes a plurality pads and aplurality of pad openings (e.g., as shown in FIGS. 3A-3B). The baselayer may be disposed above the top surface of the housing body (e.g.,as shown in FIGS. 3A-3B). The horizontal portions of the plurality ofinterconnects may be coupled to the plurality of pads of the base layer(e.g., as shown in FIGS. 1 and 3A-3B). For example, the interconnects ofthe TL-LGA socket are coupled to the pads of the package as such theTL-LGA socket may be used to couple the TL-LGA socket to an integratedcircuit (e.g., a microprocessor, a central processing unit (CPU), a die,etc.).

Additional embodiments of the TL-LGA socket may include the horizontalportions of the plurality of interconnects disposed between the baselayer of the package and the top surface (or the top conductive layer)of the housing body (e.g., the horizontal portion, the base layer, andthe top surface of the housing body are parallel to each other as shownin FIG. 3B). For some embodiments, the TL-LGA socket may include aplurality of solder balls disposed on the bottom surface of the housingbody (e.g., as shown in FIGS. 1, 4, and 5A-5B). The plurality of solderballs may be used to couple the TL-LGA socket to a substrate (e.g., aprinted circuit board (PCB)). For one embodiment, a ground reference maybe used to couple to only the base layer of the package. In thisembodiment, when only the base layer is coupled to a ground reference,the horizontal portion of the TL-LGA socket is parallel to the groundreference of the base layer, and thus the horizontal portion isimplemented as a microstrip (i.e., the horizontal portion is (oracts/behaves/performs as) a type of microstrip). For an alternativeembodiment, one or more ground references may be used to couple to boththe base layer of the package and the top surface of the housing body.In this alternative embodiment, when both the base layer and the topsurface of the housing body are coupled to the ground references, thehorizontal portion of the TL-LGA socket is parallel to both the groundreferences of the base layer the top surface of the housing, and thusthe horizontal portion is implemented as a stripline (i.e., thehorizontal portion is (or acts/behaves/performs as) a type ofstripline).

Additionally, for some embodiments, the package has the base layer thatincludes pad openings and pads (e.g., as shown in FIG. 3A). For example,a TL-LGA interconnect may have the vertical portion extend in thehousing body from or near the top surface to the bottom surface (i.e.,the vertical portion extends in the housing body in a z-direction),where the top end of the vertical portion may couple to the horizontalportion, and the bottom end of the vertical portion may couple to asolder ball (e.g., as shown in FIGS. 1 and 5B). For these embodiments,the interconnect of the TL-LGA socket may have one end of the horizontalportion coupled to the top end of the vertical portion (thus forming atransmission line in the TL-LGA socket), and may have the other/oppositeend of the horizontal portion coupled to the pad of the package, whichmay be positioned and exposed in a pad opening of the base layer.

Embodiments of the TL-LGA socket improve semiconductor packagingsolutions by enabling an LGA socket to meet the stricter requirements,such as the data rate demand and scalability, for through-sockethigh-speed inputs/outputs (IOs) (HSIOs) needed in the next-generationserver and client products. Furthermore, the embodiments of the TL-LGAsocket help to extend the life span of the LGA and multi-generationpotential products as a low cost socket solution. For example, theseembodiments provide a TL-LGA socket to satisfy the next-generationthrough-socket HSIOs (e.g., peripheral component interconnect express(PCIe) G5) that can operate roughly at 32 Gb/s or higher and that posechallenging channel electrical budgets (e.g., this drives a largeelectrical budget reduction at a higher frequency for every component inthe channel, including the socket).

Embodiments of the TL-LGA socket enhance electrical socket connectorstructures by (i) improving the electrical performance andcharacteristics such as improved bandwidth and data rate speeds, reducedreturn and insertion losses, and decreased impedance mismatch; (ii)significantly reduced assembly cost; (iii) increased potential forproduct generation scaling and cost reduction; (iv) curbing the need forheight reduction and design challenges; and (v) redefining the LGAsocket design flow and methodology by implementing cascaded transmissionline structures to allow maximal electrical bandwidth and thus focusingon the electrical performance rather than the mechanical design as thestarting point of the LGA socket design flow and methodology. Note that,for example, by redefining the LGA socket flow and methodology, theembodiments of the TL-LGA socket may facilitate/enhance the PCIecapabilities (e.g., the PCIe G5 capabilities) by enabling higher datarate speeds and thus providing more diversified and superiorapplications for consumer next-generation products.

Accordingly, the embodiments described herein improve the LGAsocket/connector which is usually associated as a lumped electricalcomponent with parasitic characteristics, such as inductance andcapacitance. For example, the inductance and capacitance particularlydetermine the impedance of the LGA socket and therefore the return lossand insertion loss at a high frequency range establishes the electricalperformance for the respective LGA socket. Here, the embodiments of theTL-LGA socket achieves good electrical performance over a broadbandwidth by (i) reducing the parasitic inductance and capacitance toavoid resonance, and (ii) maintaining the ratio of parasitic inductanceand capacitance for a relatively constant impedance profile over abroadband of frequency. This is achieved by implementing a transmissionline in the embodiments of the TL-LGA socket, as the transmission linefacilitates the features and design rules of each segment of the TL-LGAsocket with a cascaded transmission line process (i.e., this ensures theelectrical performance of the TL-LGA socket is optimized by using theone or more cascaded transmission line segments).

Certain features of various embodiments are described herein withreference to the use of a TL-LGA socket (or connector) to couple an ICdevice and a package substrate. However, such description may beextended to additionally or alternatively apply to any of a variety ofother applications where, for example, TL-LGA socket is to couple to anyIC device and/or circuit board. The technologies described herein may beimplemented in one or more electronic devices. Non-limiting examples ofelectronic devices that may utilize the technologies described hereininclude any kind of mobile device and/or stationary device, such ascameras, cell phones, computer terminals, desktop computers, electronicreaders, facsimile machines, kiosks, netbook computers, notebookcomputers, interne devices, payment terminals, personal digitalassistants, media players and/or recorders, servers (e.g., blade server,rack mount server, combinations thereof, etc.), set-top boxes, smartphones, tablet personal computers, ultra-mobile personal computers,wired telephones, combinations thereof, and the like. Such devices maybe portable or stationary. In some embodiments, the technologiesdescribed herein may be employed in a desktop computer, laptop computer,smart phone, tablet computer, netbook computer, notebook computer,personal digital assistant, server, combinations thereof, and the like.More generally, the technologies described herein may be employed in anyof a variety of electronic devices including a TL-LGA socket to couplean IC device (e.g., an IC chip/die) and/or the package substrate to asubstrate (e.g., a motherboard, a PCB, etc.) or other such motherboarddevice/board/card.

In the following description, various aspects of the illustrativeimplementations will be described using terms commonly employed by thoseskilled in the art to convey the substance of their work to othersskilled in the art. However, it will be apparent to those skilled in theart that the present embodiments may be practiced with only some of thedescribed aspects. For purposes of explanation, specific numbers,materials and configurations are set forth in order to provide athorough understanding of the illustrative implementations. However, itwill be apparent to one skilled in the art that the present embodimentsmay be practiced without the specific details. In other instances,well-known features are omitted or simplified in order not to obscurethe illustrative implementations.

Various operations will be described as multiple discrete operations, inturn, in a manner that is most helpful in understanding the presentembodiments, however, the order of description should not be construedto imply that these operations are necessarily order dependent. Inparticular, these operations need not be performed in the order ofpresentation.

FIG. 1 is a cross-section view of a transmission line 100 having avertical portion 110 and a horizontal portion 120, according to oneembodiment. For one embodiment, the transmission line 100 may be asingle TL-LGA socket interconnect 103 (or a TL-LGA socket pin) of aplurality of interconnects (e.g., as shown in FIG. 4), where theplurality of interconnects may be disposed in/on the TL-LGA socket.

According to some embodiments, the transmission line 100 includes twomain components: the vertical portion 110 and the horizontal portion 120(or a planar cantilever). For one embodiment, the vertical portion 110may be disposed in a housing body/cavity (e.g., as shown in FIGS. 5A-5B)of the TL-LGA socket. For one embodiment, the vertical portion 110 mayhave a cylindrical outer surface surrounding a pin (or a socket pin),where the vertical portion 110 may have a hollow body within thecylindrical outer surface (e.g., as shown in FIGS. 5A-5B). For oneembodiment, the horizontal portion 120 may have a planar rectangularshape. For one embodiment, the horizontal portion 120 may be a planarcantilever 120 having a first connector 121 and a second connector 122on opposite ends of the planar cantilever 120, where the horizontalportion 120 is coupled (and perpendicular) to the vertical portion 100and may be partially or fully exposed in the air (e.g., as shown in FIG.3B). According to some embodiments, the vertical portion 110 and thehorizontal portion 120 may be designed with different transmission linefeatures and characteristics based on their structure and surroundingfeature(s).

The vertical portion 110 may be disposed (or formed) as a coaxial cabletransmission line. The vertical portion 110 may have a cylindricalshape/member (i.e., a coaxial cable shape) which may reduce the need fora socket z-height reduction. Note that the vertical portion 110 is notlimited to a cylindrical shape and may have any other shape based on thedesired TL-LGA packaging design, which include other shapes such aspolygonal, sphere, hexagon, circular, and/or square. For someembodiments, the vertical portion 110 may be implemented as an innerconductor and an outer conductor (described in further detail below inFIGS. 2A-2B). The vertical portion 110 may include a cylindrical outersurface that houses a socket pin (e.g., as shown in FIG. 5B), where thecylindrical outer surface may be formed of a liquid-crystal polymer(LCP) material.

The horizontal portion 120 may be implements, but not limited to, as astripline and/or a microstrip. For some embodiments, the horizontalportion 120 of the TL-LGA socket is the horizontal portion of thetransmission line 100, which may be illustrated as having a planarcomponent/structure in the form of a microstrip (with a ground referenceonly on a base layer of the package) or the stripline (with the groundreference(s) on both a base layer of a package, and a conductive layer(or metal plating) of a top surface of a housing body of the TL-LGAsocket). For one embodiment, the package may be, but not limited to, anysemiconductor package, packaging enclosure, package substrate, and thelike. Furthermore, these planar components allow the mechanical designneeds of the TL-LGA socket to meet the electrical requirements,resulting from a planar/horizontal cantilever that is parallel to groundreference(s) under a normal loading condition.

For example, the horizontal portion 120 may be a planar cantilever 120that is coupled to the vertical portion 110 with the first connector121, and coupled to a pad (or LGA pad) on the base layer of the packagewith the second connector 122. For one embodiment, the first connector121 and the second connector 122 have circular shapes that extendsvertically on opposite ends of the horizontal portion 120 (i.e., thefirst connector 121 extends vertically to couple the vertical portion110 to the planar cantilever 120, and the second connector 122 extendsvertically to couple the planar cantilever 120 to the pad on the baselayer of the package). For one embodiment, the second connector 122 mayhave an exposed top surface that is parallel to the planar cantilever120. For example, the exposed top surface of the second connector 122 ofthe horizontal portion 120 may be coupled to the pad on the conductivebase layer of a package, where the pad is disposed in a correspondingpad opening on the conductive base layer of the package, and where theconductive base layer is above the conductive layer of the housing body(e.g., as shown in FIGS. 3A-3B).

Note that, as shown in FIG. 1, the connectors 121-122 are illustrated asseparate components that are used to couple the vertical portion 110,the horizontal portion 120, and the pad (as shown in FIGS. 3A-3B), butthe transmission line 100 may be formed without the connectors 121-122based on the desired packaging design (e.g., as shown in FIGS. 5A-5B).Also note that the horizontal portion 120 may be referred to as theplanar cantilever 120.

In one embodiment, the transmission line 100 may have the horizontalportion 120 formed with stamp-metal manufacturing processes (e.g., toattain an optimized differential impedance for the transmission linedesign, a TL-LGA socket may have a height of less than roughly 2.7 mm,and a horizontal portion may have a thickness of less than roughly 80um, a width of less than roughly 250 um, and a distance between a groundconductive base layer of a package and a ground conductive layer on ahousing body of less than roughly 100 um). Note that the medium inbetween the top and bottom ground conductive layers may be air.

For some embodiments, a plurality of TL-LGA interconnects may be formedby cascading vertical portions (e.g., vertical portion 110) andhorizontal portions (e.g., horizontal portions 120)—which comprise(and/or are represented as) a plurality of transmission lines (e.g.,transmission line 100) with one or more small vertical cylindricaltransitions coupled with solder balls (e.g., solder ball 105). Accordingto some embodiments, the vertical portion can be a hollowstructure/member with a variety of cross-section shapes (e.g., variousvertical cylindrical members/connections can be optimized to meet themechanical needs). In addition, the vertical portion may behave one ormore slots to facilitate the mechanical needs/requirements as long asouter contour/surface remains roughly unchanged. Likewise, the geometryof the cantilever (or the horizontal portion) can be further tuned aslong as the impedance profile also remains roughly unchanged.

According to some embodiments, the package may have the conductive baselayer that has the pad in a corresponding pad opening, leaving a smallgap between the pad and the corresponding pad opening of the base layer(e.g., as shown in FIG. 3A). For some embodiments, the base layer may begrounded and provide the only grounding needed for the TL-LGA socket,where the horizontal portion 120 is to be implemented/disposed as amicrostrip. However, for other embodiments, the base layer and the topsurface of the housing body are parallel to each other (e.g., as shownin FIG. 3A), where both the base layer and the top surface of thehousing body are grounded. In these other embodiments, the base layer isgrounded, and the top surface of the housing body may also be groundedwith a grounded metal plating on the top surface of the housing body, assuch the horizontal portion 120 is to be implemented/disposed as astripline. For example, the grounded top surface of the housing body mayinclude a conductive layer that is formed with (i) metal platingconnected to ground contacts, and (ii) metal plating insulated from anyof the signal contacts. For some embodiments, the planar cantilever ofthe horizontal portion 120 has a planar structure which is parallel toand in between both the conductive layers of the housing body and thepackage. That is, for example unlike existing technologies of a LGAsocket pin having a spring-like wavy, horizontal section, a majority ofthe horizontal portion 120 of the TL-LGA interconnect 100 is aflat/straight surface formed in one plane that may be parallel to theconductive layers of the housing body and the package.

Note that the transmission line 100 of the TL-LGA socket of FIG. 1 mayinclude fewer or additional packaging components based on the desiredpackaging design.

FIG. 2A is a top, perspective view of a first coaxial cable 200 having aplurality of vertical portions with a signal pin 211 and ground pins 210a, according to embodiment. FIG. 2B is a top, perspective view of asecond coaxial cable 250 having a plurality of inter-stitched groundplated-through holes (PTHs) 240 surrounding a TL-LGA vertical portionwith a signal pin 211, and a plurality of TL-LGA vertical portions withsignal pins 210 b surrounding the inter-stitched ground PTHs 240 and thesignal pin 211, according to embodiment.

As shown in FIG. 2A, the first coaxial cable 200 illustrates a pluralityof TL-LGA vertical portions with ground pins 210 a having a firstcoaxial cable design that uses adjacent ground pins 210 as groundreferences (shown with a pattern of closely-spaced diagonal stripes in abackslash direction) that surround the signal pin 211. As shown in FIG.2B, the second coaxial cable 250 illustrates a plurality of TL-LGAvertical portions with signal pins 210 b having a second coaxial cabledesign that uses ground PTHs 240 as ground references (shown with apattern of closely-spaced diagonal stripes in a backslash direction)that surround the signal pin 211, where the adjacent signal pins 210 bsurround the ground PTHs 240 and the signal pin 211.

For some embodiments, the vertical portions 210 a-b and 211 of a TL-LGAsocket of FIGS. 2A-2B may be similar to the vertical portion 110 theTL-LGA socket of FIG. 1. Note that FIGS. 2A-2B only shows the verticalportions for simplicity and illustration purposes of the coaxial cabledesigns, but the TL-LGA socket includes additional components (e.g.,cantilevers, pads, base layer, housing body, etc.).

For some embodiments, the vertical portions 210 a-b and 211 of theTL-LGA socket have vertical cylindrical shapes, where the verticalportions 210 a-b and 211 are positioned as transmission linesrepresenting a coaxial cable design. The coaxial cable designimplemented in the TL-LGA socket reduces the need for socket heightreduction. The coaxial cable has an inner conductor (e.g., signal pin211) and one or more outer conductors (e.g., adjacent ground pins 210 aof FIG. 2A, and/or the ground PTHs 240 of FIG. 2B). Note that, as shownin FIGS. 2A-2B, the vertical portions 210 a-b and 211 are positionedwith a coaxial design that also has a cascaded pattern/configuration,but the vertical portions may be positioned to have any desired shape,pattern, and/or design based on the needed packaging design andapplication.

Referring now to FIG. 2A, the coaxial cable 200 has a plurality ofvertical portions with ground pins 210 a and the signal pin 211. For oneembodiment, the signal pin 211 is the inner conductor which may beillustrated as a signal socket interconnect (pin/contact). The signalpin 211 (or the vertical portion with the signal pin) may be surroundedwith the ground pins 210 a (or the adjacent vertical portions with theground pins). For some embodiments, the adjacent signal pins 210 a areground references and form the outer conductor illustrated as adjacentground references (shown with a pattern of closely-spaced diagonalstripes in a backslash direction). Note that the outer conductor may beformed with five adjacent ground pins 210 a, but may include more orless than five adjacent ground pins based on the desired packagingdesign. Accordingly, the first coaxial cable 200 has the outer conductor(shown as having a “D” value/length) and the inner conductor (shown ashaving a “d” value/radius). The characteristic impedance of the coaxialcable is determined by the outer “D” value and the inner “d” radius ofthe conductors. The values of “D” and “d” of the TL-LGA socket areselected and disposed based on, but not limited to, the impedancetarget, the various ground reference scenarios (e.g., one groundreference scenario is shown in FIG. 2A, and another ground referencescenario is shown in in FIG. 2B), the housing material dielectricconstant, the pin-to-pin pitch, the pin map pattern (e.g., cascadingpattern), and the overall interconnect shape/design.

Note that the first coaxial cable 200 of the TL-LGA socket of FIG. 2Amay include fewer or additional packaging components based on thedesired packaging design.

Referring now to FIG. 2B, the second coaxial cable 250 has a pluralityof vertical portions with signal pins 210 b and the signal pin 211,including the adjacent signal pins 210 b surrounding the ground PTHs 240which surround the signal pin 211. Note that—unlike the ground verticalportions 210 a of FIG. 2A—the vertical portions 210 b are signal pins(shown with a pattern of intersecting diagonal stripes) and not groundreferences. For one embodiment, the signal pin 211 is the innerconductor which may be illustrated as a signal socket interconnect. Thesignal pin 211 may be surrounded with the ground PTHs 240 and theadjacent signal pins 210 b. For some embodiments, the signal pins 210 bmay be used as additional transmission lines rather than as groundreferences, which may maximize the bandwidth and data rate speeds of theTL-LGA socket.

According to some embodiments, the ground PTHs 240 are ground referencesand form the outer conductor illustrated as smaller adjacent PTHs (shownwith a pattern of closely-spaced diagonal stripes in a backslashdirection). For one embodiment, the inter-stitched ground PTHs 240 maybe plated holes/vias (e.g., drilled holes) disposed on a top surface (ora top conductive layer) of a housing body that are closely-spaced,grounded, and coupled together as ground references. Accordingly, thesecond coaxial cable 250 has the outer conductor (shown as having a “D”value/length) and the inner conductor (shown as having a “d”value/radius). This second coaxial cable 250 design provides additionalpin-to-pin crosstalk reduction benefit, as the characteristic impedanceof the TL-LGA socket is changed, by reducing the value of “D” and stillmaintaining the coaxial design with the cascading pattern.

Note that the second coaxial cable 250 of the TL-LGA socket of FIG. 2Bmay include fewer or additional packaging components based on thedesired packaging design. Also note that the TL-LGA socket of FIG. 2Bmay be different than the TL-LGA socket of FIG. 2A, even if both TL-LGAsockets include similar packaging/socket components.

FIG. 3A is a top, perspective view of a package 350 having a base layer301 with a pad 330, and a TL-LGA socket 300 including a housing body302, a conductive layer 302 a, and an interconnect 303 (or atransmission line) having a vertical portion 310 and a cantilever 320,according to one embodiment. FIG. 3B is a cross-sectional view of thepackage 350 having the base layer 301 with the pad 330, and the TL-LGAsocket 300 including the interconnect 303 with the cantilever 320 andthe conductive layer 302 a of the housing body 302, according to oneembodiment. The TL-LGA socket 300 of FIGS. 3A-3B may be similar to theTL-LGA sockets of FIGS. 1 and 2A-2B. Note that FIGS. 3A-3B only showsportions of the TL-LGA socket 300 for illustrative simplicity, but theTL-LGA socket 300 may include additional components.

For some embodiments, the TL-LGA socket 300 may include a plurality ofinterconnects 303, but for illustrative simplicity, a portion of asingle interconnect 303 (e.g., similar to the interconnect 100 ofFIG. 1) is shown. Each of the plurality of interconnects 303 of theTL-LGA socket 300 may include the vertical portion 310 (note that onlythe top end is shown in FIG. 3A) and the cantilever 320 (or a horizontalportion), and the cantilever coupled to the pad 330 of the package 350.According to some embodiments, the TL-LGA socket 300 may include ahousing body 302 having a top surface, such as the conductive layer 302a) and a bottom surface (not shown) that is opposite from the topsurface, as each of the vertical portions (e.g., vertical portion 310)of the plurality of interconnects 303 is disposed in the housing body320. Additionally, for some embodiments, the plurality of interconnects303 of the TL-LGA socket 300 may be disposed in the housing body 302 toform a plurality of cascaded transmission lines 303 (e.g., as shown inFIG. 4). For some embodiments, the top surface of the housing body 302is a conductive layer 302 a that has one or more openings 306, where theopenings 306 are positioned above the top end of the vertical portions310.

For one embodiment, the package 350 may include a base layer 301 (or abottommost layer/surface of the package 350) having a plurality ofcorresponding pad openings 305 and a plurality of pads 330, where thebase layer 301 is disposed above the top conductive layer 302 a of thehousing body 302. Accordingly, the vertical portion 310 and thecantilever 320 of the TL-LGA socket 300 are coupled to the pad 330 ofthe base layer 301 of the package 350, thereby implementing/forming atransmission line 303.

For one embodiment, the TL-LGA socket 300 may be a LGA device/socketthat has been disposed/formed with cascaded transmission line 303structures to improve (or maximize) the bandwidth and data rate speedsof the TL-LGA socket 300. Additionally, the base layer 301 has one ormore pad openings 305, where each of the pad openings 305 houses one ofthe pads 330 of the plurality of TL-LGA interconnects 303. For example,the TL-LGA transmission line 303 may have the vertical portion 310extend in the housing body 302 from or near the conductive layer 302 ato the bottom surface (not shown), where the top end of the verticalportion 302 may couple to the cantilever 320 with a connector 321, andthe bottom end of the vertical portion 302 may couple to a solder ball(e.g., as shown in FIGS. 5A-5B). As such, for these embodiments, thecantilever 320 is disposed between the base layer 301 of the package 350and the conductive layer 302 a of the housing body 302 (i.e., thecantilever 320, the base layer 301, and the conductive layer 302 a ofthe housing body 302 are parallel to each other, as shown in FIG. 3B).Based on this parallel design/structure of the transmission line (orinterconnect), the cantilever 320 may be implemented/designed to be atleast one of a stripline and a microstrip based on the ground referencesof the TL-LGA socket 300.

As shown in FIGS. 3A-3B, the cantilever 320 may be a stripline as theground references are on both the base layer 301 and the conductivelayer 302 a of the housing body 302 (i.e., the base layer 301 and theconductive layer 302 a are both grounded). For one embodiment, thetransmission line 303 of the TL-LGA socket 300 has one end of thecantilever 320 coupled to the top end of the vertical portion 310 withthe connector 321, and the opposite end of the cantilever 320 is coupledto the pad 330 of the package 350 with a connector 322. For oneembodiment, the package 350 has a plurality of pad openings 305 that areformed with a cascading pattern, where the pad opening 305 may surroundthe pad 330 of the base layer 301 that is coupled to the cantilever 320.The base layer 301 may have a gap opening 309 (e.g., an opening ofroughly 50 um) between the outer edge of the pad 330 and the inner edgeof the pad opening 305. The size of the gap opening 309 may beimplemented based on the desired packaging design and electricalcharacteristics.

Referring now to FIG. 3B, the TL-LGA socket 300 illustrates thecantilever 320 portion of the interconnect 303, and the opening 306 onthe conductive layer 302 a of the housing body 302 that is used toconnect to the vertical portion 310. The cantilever 320 may be disposedin the air between the base layer 301 and the conductive layer 302 a ofthe housing body 302, as such the cantilever 320, the base layer 301,and the conductive layer 302 a are parallel to each other. In oneembodiment, when the interconnect 303 is loaded, the interconnect 303may be in a flat/horizontal position with the weight (or force) of thepackage 350 pressing down on the horizontal portion 620 of the loadedinterconnect 303.

In one embodiment, the cantilever 320 may be surrounded by a groundconductive layer 302 a of the housing body 302 and a grounded base layer301, thereby the cantilever 320 is a stripline. For one embodiment, thecantilever 320 may have a rectangular shape, but the cantilever may alsobe formed with any other design (e.g., a socket pin as shown in FIGS.5A-5B) and have any other shape (e.g., cylindrical). Note that, when theground reference is only disposed on the base layer of the package, thecantilever may be a microstrip. Also note, when the ground reference isdisposed on both the base layer of the package and the top surface ofthe housing body, the cantilever may be a stripline.

Note that the TL-LGA socket 300 of FIGS. 3A-3B may include fewer oradditional packaging components based on the desired packaging design.

FIG. 4 is a top, perspective view of a TL-LGA socket 400 having ahousing 402, a plurality of transmission lines 403, and a plurality ofsolder balls 405, according to one embodiment. The TL-LGA socket 400 ofFIG. 4 may be similar to the TL-LGA sockets of FIGS. 1, 2A-2B, and 3A-3B(e.g., the TL-LGA socket 300). Note that FIG. 4 only shows a portion ofthe TL-LGA socket 400 and omits other components of the TL-LGA socket400 to simplify the illustration, as such the TL-LGA socket 400 mayinclude additional components.

As shown in FIG. 4, the TL-LGA socket 400 includes a plurality oftransmission lines 403 disposed in the housing body 402 as thetransmission lines 403 are patterned to form the plurality of cascadedtransmission lines 403. The TL-LGA socket 400 helps to improve the LGAtechnologies and designs by approximating each critical portion of thesocket pin (or the TL-LGA interconnect) as cascaded transmission lines403 in the housing body 402.

The TL-LGA socket 400 may include a plurality of vertical portions 410,each vertical portion 410 extending from the bottom surface to theconductive layer 402 a (or the top surface) of the housing 402. For oneembodiment, the bottom end of the vertical portion 410 is coupled to asolder ball 405, and the top end of the vertical portion 410 is coupledto a connector 421. The connector 421 may be coupled to the cantilever420, and the cantilever 420 may be coupled to a connector 422. For oneembodiment, the connector 422 is coupled to a pad 430 which issurrounded by an opening (not shown) in a base layer 401 of a package450. Additionally, the solder ball 405 of the TL-LGA socket 400 may becoupled with a substrate 451.

According to some embodiments, the substrate 451 may include, but is notlimited to, a package substrate, a substrate, a printed circuit board(PCB), and a motherboard. For one embodiment, the substrate 451 is aPCB. For one embodiment, the PCB is made of an FR-4 glass epoxy basewith thin copper foil laminated on both sides (not shown). For certainembodiments, a multilayer PCB can be used, with pre-preg and copper foil(not shown) used to make additional layers. For example, the multilayerPCB may include one or more dielectric layers, where each dielectriclayer can be a photosensitive dielectric layer (not shown). For someembodiments, holes (not shown) may be drilled in the PCB 451. For oneembodiment, the PCB 451 may also include conductive copper traces,metallic vias/pads, and holes (not shown).

Note that the TL-LGA socket 400 of FIG. 4 may include fewer oradditional packaging components based on the desired packaging design.

FIG. 5A is a top, perspective view of a transmission line 503 of aTL-LGA socket 500 having a vertical portion 510, a cantilever 520, acontact 530, and a solder ball 505, according to one embodiment. FIG. 5Bis a cross-sectional view of a transmission line 503 of the TL-LGAsocket 500 having the vertical portion 510, the cantilever 520, thecontact 530, and the solder ball 505 according to one embodiment. TheTL-LGA socket 500 of FIG. 5 may be similar to the TL-LGA sockets ofFIGS. 1, 2A-2B, 3A-3B, and 4. Note that FIG. 5 only shows a portion ofthe TL-LGA socket 500 and may omit other components of the TL-LGA socket500 to simplify the illustration, as such the TL-LGA socket 500 mayinclude additional components (e.g., a base layer).

FIG. 5A illustrates a socket pin 511 disposed in the vertical portion510, according to some embodiments. The socket pin 511 may be coupled tothe cantilever 520, and the cantilever 520 may be coupled to the socketcontact 530. For some embodiments, the geometry (or design) of thecantilever 520 portion can be further tuned (i.e., the cantileverportion may have other shapes notwithstanding a rectangular, horizontalportion) as long as the impedance profile remains unchanged. FIG. 5Billustrates the socket pin 511 extending the z-height of the verticalportion 520, as the socket pin 511 is coupled to the solder ball 505 andthe cantilever 520, which protrudes from inside the vertical portion 520through an opening 506 in the conductive layer 502 a (or the topsurface) of the housing body 502.

Note that the TL-LGA socket 500 of FIGS. 5A-5B may include fewer oradditional packaging components based on the desired packaging design.

FIG. 6A is a plan view of a TL-LGA socket assembly having a package 650with a base layer 601 that includes a flooded ground plane 601 a, aplurality of pads 630, and a plurality of corresponding pad openings605, and a TL-LGA socket including a plurality of TL-LGA interconnects603 with horizontal portions 620, according to embodiment. FIG. 6B is aplan view of only the package 650 with the base layer 601 that includesthe flooded ground plane 601 a, the plurality of pads 630, and theplurality of corresponding pad openings 605, according to embodiment.The TL-LGA socket of the TL-LGA socket assembly 600 of FIG. 6A may besimilar to the TL-LGA sockets of FIGS. 1-5. Note that FIGS. 6A-6B onlyshows a portion of the TL-LGA socket assembly 600 and may omit othercomponents of the TL-LGA socket and the package to simplify theillustration, as such the TL-LGA socket assembly 600 may includeadditional components (e.g., a housing body, a vertical portion, an ICdie, etc.).

For one embodiment, the TL-LGA socket assembly 600 includes aninterconnect 603 with a horizontal portion 620 of the TL-LGA socket. Theinterconnect 603 may include a solder ball, a vertical portion, and ahorizontal portion 620 (e.g., as shown in FIG. 1). For an additionalembodiment, the TL-LGA socket assembly 600 further includes a package650 (or a package substrate) with a base layer 601, where the base layer601 includes pads 630 and corresponding pad openings 605. The base layer601 of the package 650 may be disposed as the bottommost layer of thepackage 650 and disposed above a conductive layer of a housing body ofthe TL-LGA socket (e.g., as shown in FIGS. 3A-3B and 8). The pads 630 onthe base layer 601 may be signal pads 640 and/or grounded pads 641. Forone embodiment, the horizontal portion 620 of the interconnect 603 (or atransmission line) may be coupled to the signal pad 640 on the baselayer 601, as the ground plane 601 a (or the flooded ground plane)floods the base layer 601 with a ground reference(s) ant the floodedground plane 601 a is disposed above and parallel to the horizontalportion 620 of the interconnect 603 to create the transmission linestructures of the TL-LGA socket assembly 600.

As used herein, a “flooded ground plane” refers to a ground plane with aground reference (e.g., a ground plate, a ground contact/pin, ground,etc.), which floods the base layer of the package to be grounded withvoids (or openings) around one or more pads (e.g., the signal pads 640,power pads, etc.). For example, the flooded ground plane 601 a may becoupled to the ground pads 641 on the base layer 601, where the floodedground plane 601 a may include pad openings 605 to surround signal pads640.

For some embodiments, the TL-LGA socket assembly 600 may include thepackage 650 having the pads 630 with a LGA pad area reduction of greaterthan roughly 50% of existing LGA pad sizes (e.g., the pads 630 may havea pad area reduction of greater than roughly 50% a LGA pad withdimensions of roughly 0.33 mm×0.40 mm), which allows the flooded groundplane 601 a to flood (or couple) the non-signal land pad area withground (i.e., the land pad area of the pads 630 have been reduced by 50%or more). For example, rather than typically attaining the electricallydesired ground area by using larger LGA ground pads, the package 650 ofthe TL-LGA socket assembly 600 may reduce the LGA land pad area of eachpad 630 by using the ground reference of the flooded ground plane 601a—and thus enabling the land pad area of the pads 630 to be reduced.

For some embodiments, the TL-LGA socket assembly 600 may have asingle-sided ground reference for the horizontal portion 620 thatenables the horizontal portion 620 of the interconnect/transmission line603 to have microstrip electrical characteristics, which helps improvethe loss/reflection/impedance electrical performances of the TL-LGAsocket assembly 600. For example, with the flooded ground plane 601 a,the impedance discontinuity of the pads 630 of the TL-LGA socketassembly 600 may be reduced by 21 Ohms (or more than 21 Ohms) ascompared to an existing LGA pad. For one embodiment, the signal pad 640may be coupled to the horizontal portion 620 forming the interconnect603 that transmits a signal. Likewise, for one embodiment, the groundpads 641 may be coupled to the flooded ground plane 601 a of the baselayer 601 on the package 650. In one embodiment, the flooded groundplane 601 a may surround the pad openings 605 and the signal pads 640,leaving gap openings 609 between the signal pads 640 and thecorresponding pad openings 605. For one embodiment, the gap openings 609may have an opening length 618 of less than roughly 50 um between thesignal pads 640 and the corresponding pad openings 605.

For one embodiment, the flooded ground plane 601 a on the base layer 601may be coupled to the ground pads 641. In this embodiment, the floodedground plane 601 a is parallel to the horizontal portions 620, whichallows the horizontal portion 620 and the vertical portion to form thetransmission line 603 of the TL-LGA socket assembly 600. Additionally,the TL-LGA socket assembly 600 improves packaging solutions by avoidingadditional plating processes using the flooded ground plane 601 a on thebase layer 601, which reduces the assembly time, reduces cost and risks,and improves the data rate speeds and bandwidth of the TL-LGA socketassembly 600.

FIG. 6B omits one or more components and only shows the top view of thepackage 650 with the base layer 601 of the TL-LGA socket assembly 600 tosimplify the illustration. For one embodiment, the signal pads 640 areshown with a dashed line to illustrate their position on the base layer650. Note that, the flooded ground plane 601 a of the base layer may beformed of a conductive material (e.g., Cu or the like).

Note that the TL-LGA socket assembly 600 of FIGS. 6A-6B may includefewer or additional packaging components based on the desired packagingdesign.

FIG. 7A is a plan view of a TL-LGA socket assembly 700 including apackage 750 with a base layer 701 having a plurality of ground strips751 a-b and a plurality of pads 730, and a TL-LGA socket with aplurality of TL-LGA interconnects 703 having horizontal portions 720,according to embodiment. FIG. 7B is a plan view of the TL-LGA socketassembly 700 including the package 750 having the base layer 701 thatincludes the ground strips 751 a-b and the signal pads 740, according toembodiment. The TL-LGA socket of the TL-LGA socket assembly 700 of FIG.7A may be similar to the TL-LGA sockets of FIGS. 1-6A, but the TL-LGAsocket assembly 700 of FIGS. 7A-7B further includes ground strips 751a-b that are selectively disposed above the horizontal portions 720 ofthe high-speed interconnects 703 (or high-speed socket signals/pins).For example, instead of the TL-LGA socket assembly 600 of FIGS. 6A-6Bwhich includes the flooded ground plane 601 a on the base layer 601 ofthe package 650, the TL-LGA socket assembly 700 of FIGS. 7A-7B includesreduced/isolated ground pads 741 and selectively positioned groundstrips 751 a-b that are disposed only above the horizontal portions 720of the high-speed interconnects 703. Note that, as shown in FIGS. 7A-7B,two ground strips 751 a-b are illustrated, but a package of the TL-LGAsocket assembly may have one or more grounds strips based on the desiredpackaging design. Also note that FIGS. 7A-7B only shows a portion of theTL-LGA socket assembly 700 and may omit other components of the TL-LGAsocket assembly 700 to simplify the illustration, as such the TL-LGAsocket assembly 700 may include additional components (e.g., a housingbody, a vertical portion, an IC die, etc.).

For one embodiment, the TL-LGA socket assembly 700 includes aninterconnect 703 of the TL-LGA socket (e.g., as shown in FIGS. 1, 3A-3B,4, 5A-5B, and 8). The interconnect 703 may include a vertical portioncoupled to a horizontal portion 720 (e.g., as shown in FIG. 1). In oneembodiment, the TL-LGA socket assembly 700 also includes a package 750having a base layer 701 which includes pads 730 and ground strips 751a-b. For one embodiment, the pads 730 may include, but is not limitedto, signal pads 740, ground pads 741, and power pads. According to oneembodiment, the TL-LGA socket assembly 700 further includes the groundstrips 751 a-b that are on the base layer 701, where the ground strips751 a-b are positioned over the horizontal portions 720 of theinterconnects 703 and are adjacent to the signal pads 740, and where thehorizontal portions 720 of the interconnects 703 of the TL-LGA socketare coupled to the signal pads 740.

As shown in FIGS. 7A-7B, the ground reference of the base layer 701 isnot flooded throughout the base layer 701, rather the ground strips 751a-b are only selectively formed on the base layer 701 and positionedabove the horizontal portions 720 of the high-speed interconnects 703.The TL-LGA socket assembly 700 thus reduces the impedance discontinuitythat may be caused by the ground of the base layer 701, while stillmaintaining the ground reference needed for the horizontal portions 720to create the transmission lines 703 (or interconnects).

For one embodiment, the width 729 of the ground strips 751 a-b may needto extend beyond the width of the horizontal portions 720 while alsoleaving enough space, such as the gap opening 719, for the adjacentsignal pads 741. For one embodiment, the width 729 of the ground strips751 a-b may less than roughly 400 um. For one embodiment, the length ofthe ground strips 751 a-b may vary based on the length of the horizontalportions 720, as the ground strips 751 a-b may need to cover most of thelength of the horizontal portions 720 while accounting the length of thegap openings 719 between the signal pads 740 and the horizontal portion720.

For an additional embodiment, the length of the ground strip 751 a mayneed to extend over a majority of the length of the horizontal portion720, but the edge of the ground strip 751 a closest/nearest to therespective signal pad 740 may need to leave the gap opening 719 ofroughly 250 um or greater to the respective signal pad 740 (note that,as shown in FIGS. 7A-7B, the edge of the ground strip 751 a that isclosest to the respective signal pad 740 is the bottommost edge of theground strip 751 a). For example, as shown in FIGS. 7A-7B with thedouble-side arrows, the gap opening 719 is measured from the edge of thesignal pad 740 to the closest/adjacent edge of the ground strip 751 a.

In some embodiments, the ground strips 751 a-b may be connected/coupledto one of the adjacent ground pads 741 in, but not limited to, alongitudinal direction/axis and an orthogonal direction/axis. For oneembodiment, the pads 730 and the ground strips 751 a-b are formed/platedwith a conductive material (e.g., Cu or the like) on the same bottommostbase layer 701 of the package 750, where the unoccupied area on the baselayer 701 (shown as the white unoccupied space in FIG. 7A) may include asolder resist, a solder mask, and/or the like. For another embodiment,the base layer 701 may be formed of one or more stacked layers, wherethe ground strips may be formed on one layer disposed on (above and/obelow) another layer having the pads. For example, the ground strips 751a-b may be coupled to one of the adjacent ground pads 741 using anydesired method, which is allowed by package design and manufacturingrules. For one embodiment, the ground strips 751 a-b are coupled usingtwo methods: (i) the ground strip 751 a is coupled in a longitudinaldirection/axis with the ground pad 741 as the topmost edge of the groundstrip 751 a couples the bottom surface of the ground pad 741; and (ii)the ground strip 751 b is coupled in an orthogonal direction/axis withthe ground pad 741 as the right edge of the ground strip 751 b couplesthe left side edge of the ground pad 741 with a ground via 718 (or aconductive line/trace). For one embodiment, the ground strips 751 a-bmay have rounded corners.

For some embodiments, by reducing the area of the needed groundreferences (such as the ground pads) using the selectively positionedground strips 751 a-ab, the TL-LGA socket assembly 700 may decrease thearea of each pad 730 in the base layer 701 of the package 750 (e.g., thepads may have dimensions of less than roughly 0.15 mm (+/−0.05 mm)×0.20(+/−0.05 mm)). Moreover, the ground strips 751 a-b are selectivelydisposed above the horizontal portions 720 to provide a reducedimpedance discontinuity (e.g., the impedance discontinuity of the pads730 of the TL-LGA socket assembly 700 may be reduced by 5 Ohms (or morethan 5 Ohms) as compared to the pads 630 the TL-LGA socket 600 with theflooded ground plane 601 a). In addition, implementing the ground strips751 a-b of the TL-LGA socket assembly 700 helps to achieve a reducedland pad capacitance, an improved impedance match, and an improvedreduced loss/reflection/impedance performance for the TL-LGA socket tosupport PCIe G5 data rate speeds—while the grounds strips 751 a-b may beformed with any conventional package design rules and layout processeswith no additional design or manufacturing risks.

FIG. 7B omits one or more components and only shows the top view of thepackage 750 with the base layer 701 of the TL-LGA socket assembly 700 tosimplify the illustration. For one embodiment, the signal pads 740 areshown with a dashed line to illustrate their position on the base layer750. Note that, the ground strips 751 a-b on the base layer 701 may beformed of a conductive material (e.g., Cu or the like) that is coupledto the ground reference(s) of the TL-LGA socket assembly 700.

Note that the TL-LGA socket assembly 600 of FIGS. 6A-6B may includefewer or additional packaging components based on the desired packagingdesign.

FIG. 8 is a cross-sectional view of an assembly 800 having an integratedcircuit die 814, a package substrate 850 with a base layer 801, a TL-LGAsocket 860, and a substrate 851, according to one embodiment. For oneembodiment, the assembly 800 may include a TL-LGA socket assembly thatmay include the integrated circuit die 814, the package substrate 850,and the TL-LGA socket 860. In addition, FIG. 8 is a cross-sectional viewof a semiconductor packaged assembly 800 having the TL-LGA socket 860 tocouple integrated circuit die 814 and the package substrate 850 to thesubstrate 851, such as a PCB, according to one embodiment. Note that thepackage substrate 850 and the TL-LGA socket 860 may be similar to thepackages and the TL-LGA sockets of FIGS. 1-7 as described herein.

For one embodiment, the assembly 800 includes the integrated circuit die814 coupled to the package substrate 850, where the package substrate850 includes a conductive base layer 801, the conductive base layer 801includes a plurality of pads 830 and a plurality of corresponding padopenings 805 surrounding the plurality of pads 830, where each padopening 805 has an opening gap 809 between the corresponding pad opening805 and the pad 830. For one embodiment, the die 814 may be coupleddirectly to the package substrate 850 or coupled to the packagesubstrate 850 via an interposer 812.

For one embodiment, the assembly 800 also includes the TL-LGA socket 860coupled to the package substrate 850. For one embodiment, the TL-LGAsocket 860 includes a plurality of interconnects, each of the pluralityof interconnects includes a vertical portion 810 and a horizontalportion 820. For one embodiment, the horizontal portions 820 may includeconnectors 821 and 822. For one embodiment, the TL-LGA socket 860 alsoincludes a housing body 802 having a top surface and a bottom surfacethat is opposite from the top surface, where the top surface is aconductive layer 802 a having a plurality of openings, where thevertical portions 810 of the plurality of interconnects are in thehousing body 802, and where the plurality of interconnects arepositioned in the housing body 802 in a cascaded configuration, wherethe conductive base layer 801 of the package substrate 850 is above theconductive layer 802 a of the housing body 802, where the horizontalportion 820 is between the conductive base layer 801 of the package 850and the conductive layer 802 a of the housing body 802, where thehorizontal portion 820 is parallel to the conductive base layer 801 ofthe package 850 and the conductive layer 802 a of the housing body 802,and where the horizontal portion 820 is coupled to the vertical portion810 and coupled to a corresponding pad 830 on the conductive base layer801 of the package substrate 850.

According to one embodiment, the semiconductor packaged assembly 800 ismerely one example of an embodiment wherein an integrated circuit die814 is coupled to a substrate 812 (e.g., an interposer) via one or morebumps/joints formed from respective microbumps. As described above, asolder joint formed by soldering of a microbump according to anembodiment may itself be referred to as a “bump” and/or a “microbump.”

For some embodiments, the semiconductor packaged assembly 800 may have adie 814 disposed on an interposer 812, where both the stacked die 814and interposer 812 are disposed on a package substrate 850. For oneembodiment, the die 814 may include, but is not limited to, asemiconductor die, an electronic device (e.g., a wireless device), anintegrated circuit, a central processing unit (CPU), a microprocessor, aplatform controller hub (PCII), a memory, and a field-programmable gatearray (FPGA). The die 814 may be formed from a material such as siliconand have circuitry thereon that is to be coupled to the interposer 812.Although some embodiments are not limited in this regard, the packagesubstrate 850 may in turn be coupled to another body, for example, asubstrate 851 such as a computer motherboard via the TL-LGA socket 860.One or more connections between the TL-LGA socket 860, the substrate851, the package substrate 850, the interposer 812, and the die814—e.g., including some or all of bumps 805, 816, and 818—may includeone or more interconnect structures and underfill layers 826 and 828. Insome embodiments, these interconnect structures (or connections) mayvariously comprise an alloy of nickel, palladium, and tin (and, in someembodiments, Cu).

Connections between the package substrate 850 and another body may bemade using any suitable structure, such as the interconnects of theTL-LGA socket 860. The package substrate 850 may include a variety ofelectronic structures formed thereon or therein. The interposer 812 mayalso include electronic structures formed thereon or therein, which maybe used to couple the die 814 to the package substrate 850. For oneembodiment, one or more different materials may be used for forming thepackage substrate 850 and the interposer 812. In certain embodiments,the package substrate 850 is an organic substrate made up of one or morelayers of polymer base material, with conducting regions fortransmitting signals. In certain embodiments, the interposer 812 is madeup of a ceramic base material including metal regions for transmittingsignals. Although some embodiments are not limited in this regard, theassembly 800 may include gap control structures 830—e.g., positionedbetween the package substrate 850 and the interposer 812. Such gapcontrol structures 830 may mitigate a change in the height of the gapbetween the package substrate 850 and the interposer 812, whichotherwise might occur during reflowing while die 814 is attached tointerposer 812. Note that the assembly 800 includes an underflowmaterial 828 between the interposer 812 and the die 814, and anunderflow material 826 between the package substrate 850 and theinterposer 812. The underflow materials (or layers) 826 and 828 may beone or more polymers that are injected between the layers.

According to some embodiments, the TL-LGA socket 860 may be coupled tothe substrate 851 with solder balls 805. For one embodiment, thesubstrate 851 may include, but is not limited to, a package, asubstrate, a printed circuit board (PCB), and a motherboard. For oneembodiment, the substrate 851 is a PCB. For one embodiment, the PCB ismade of an FR-4 glass epoxy base with thin copper foil laminated on bothsides. For certain embodiments, a multilayer PCB can be used, withpre-preg and copper foil used to make additional layers. For example,the multilayer PCB may include one or more dielectric layers, where eachdielectric layer can be a photosensitive dielectric layer. For someembodiments, holes may be drilled in the PCB 851. For one embodiment,the PCB 851 may also include conductive copper traces, metallic pads,and holes.

Note that the assembly 800 may include fewer or additional packagingcomponents based on the desired packaging design.

FIG. 9 is a schematic block diagram illustrating a computer system 900that utilizes a device package 910 with a TL-LGA socket assembly and/ora TL-LGA socket that has one or more transmission lines, according toone embodiment. FIG. 9 illustrates an example of computing device 900.Computing device 900 houses motherboard 902. For one embodiment,motherboard 902 may be similar to the substrate 451 and 851 of FIGS. 4and 8. Motherboard 902 may include a number of components, including butnot limited to processor 904, device package 910 (or semiconductorpackage), and at least one communication chip 906. Processor 904 isphysically and electrically coupled to motherboard 902. For someembodiments, at least one communication chip 906 is also physically andelectrically coupled to motherboard 902. For other embodiments, at leastone communication chip 906 is part of processor 904.

Depending on its applications, computing device 900 may include othercomponents that may or may not be physically and electrically coupled tomotherboard 902. These other components include, but are not limited to,volatile memory (e.g., DRAM), non-volatile memory (e.g., ROM), flashmemory, a graphics processor, a digital signal processor, a cryptoprocessor, a chipset, an antenna, a display, a touchscreen display, atouchscreen controller, a battery, an audio codec, a video codec, apower amplifier, a global positioning system (GPS) device, a compass, anaccelerometer, a gyroscope, a speaker, a camera, and a mass storagedevice (such as hard disk drive, compact disk (CD), digital versatiledisk (DVD), and so forth).

At least one communication chip 906 enables wireless communications forthe transfer of data to and from computing device 900. The term“wireless” and its derivatives may be used to describe circuits,devices, systems, methods, techniques, communications channels, etc.,that may communicate data through the use of modulated electromagneticradiation through a non-solid medium. The term does not imply that theassociated devices do not contain any wires, although in someembodiments they might not. At least one communication chip 906 mayimplement any of a number of wireless standards or protocols, includingbut not limited to Wi-Fi (IEEE 802.11 family), WiMAX (IEEE 802.16family), IEEE 802.20, long term evolution (LTE), Ev-DO, HSPA+, HSDPA+,HSUPA+, EDGE, GSM, GPRS, CDMA, TDMA, DECT, Bluetooth, derivativesthereof, as well as any other wireless protocols that are designated as3G, 4G, 5G, and beyond. Computing device 900 may include a plurality ofcommunication chips 906. For instance, a first communication chip 906may be dedicated to shorter range wireless communications such as Wi-Fiand Bluetooth and a second communication chip 906 may be dedicated tolonger range wireless communications such as GPS, EDGE, GPRS, CDMA,WiMAX, LTE, Ev-DO, and others.

Processor 904 of computing device 900 includes an integrated circuit diepackaged within processor 904. Device package 910 may include, but isnot limited to, one or more of a package, a substrate, and/or a PCB.Device package 910 may include an IC package coupled to a PCB using aTL-LGA socket (e.g., the TL-LGA sockets of FIGS. 1-7)—or any othercomponents from the figures described herein—of the computing device900. Further, as described herein, the device package 910 helps improvethe bandwidth, data rate speeds, and improved loss/reflection/impedanceperformance of the computing device 900 by reducing the pad sizes anddisposing a plurality of cascaded transmision lines, a flooded groundplane, and/or a ground strip in/on the TL-LGA socket assembly.

Note that device package 910 may be a single component/device, a subsetof components, and/or an entire system, as the materials, features, andcomponents may be limited to device package 910 and/or any othercomponent of the computing device 900 that may need TL-LGA sockets(e.g., the motherboard 902 and/or any other component of the computingdevice 900 may use the TL-LGA package as described herein).

For certain embodiments, the integrated circuit die may be packaged withone or more devices on a package substrate that includes a thermallystable RFIC and antenna for use with wireless communications and thedevice package, as described herein, to reduce the z-height of thecomputing device. The term “processor” may refer to any device orportion of a device that processes electronic data from registers and/ormemory to transform that electronic data into other electronic data thatmay be stored in registers and/or memory.

At least one communication chip 906 also includes an integrated circuitdie packaged within the communication chip 906. For some embodiments,the integrated circuit die of the communication chip may be packagedwith one or more devices on a package substrate that includes one ormore device packages, as described herein.

In the foregoing specification, embodiments have been described withreference to specific exemplary embodiments thereof. It should be bornein mind, however, that all of these and similar terms are to beassociated with the appropriate physical quantities and are merelyconvenient labels applied to these quantities. It will be evident thatvarious modifications may be made thereto without departing from thebroader spirit and scope. The specification and drawings are,accordingly, to be regarded in an illustrative sense rather than arestrictive sense.

The following examples pertain to further embodiments. The variousfeatures of the different embodiments may be variously combined withsome features included and others excluded to suit a variety ofdifferent applications.

The following examples pertain to further embodiments:

Example 1 is a transmission line-land grid array (TL-LGA) socketassembly, comprising: a TL-LGA socket having an interconnect in ahousing body, the interconnect includes a vertical portion and ahorizontal portion. The housing body has a top surface and a bottomsurface that is opposite from the top surface, wherein the top surfaceis a conductive layer; and a package having a base layer, the base layerincludes a signal pad and a ground strip. The base layer is above theconductive layer of the housing body of the TL-LGA socket. The groundstrip is above the horizontal portion of the interconnect of the TL-LGAsocket. The horizontal portion is coupled to the signal pad on the baselayer.

In example 2, the subject matter of example 1 can optionally include awidth of the ground strip greater than a width of the horizontalportion. The ground strip is adjacent to the signal pad.

In example 3, the subject matter of any of examples 1-2 can optionallyinclude a gap between the ground strip and the signal pad.

In example 4, the subject matter of any of examples 1-3 can optionallyinclude the ground strip coupled to a ground pad on the base layer.

In example 5, the subject matter of any of examples 1-4 can optionallyinclude the ground strip having a rectangular shape. The ground stripincludes at least one of a rounded corner and a perpendicular corner.

In example 6, the subject matter of any of examples 1-5 can optionallyinclude the ground strip coupled to the ground pad in at least one of alongitudinal axis and an orthogonal axis. The ground strip is coupled tothe ground pad in the orthogonal axis with a ground via.

In example 7, the subject matter of any of examples 1-6 can optionallyinclude the horizontal portion of the interconnect is parallel to theground strip on the base layer to create a microstrip.

In example 8, the subject matter of any of examples 1-7 can optionallyinclude the signal and ground pads on the base layer have a reduced padarea.

In example 9, the subject matter of any of examples 1-8 can optionallyinclude the base layer having a flooded ground plane, the flooded groundplane is coupled to at least one of a ground reference and the groundpad. The flooded ground plane has a corresponding pad openingsurrounding the signal pad on the base layer. The corresponding padopening includes a gap between the signal pad and the corresponding padopening.

Example 10 is a package substrate, comprising: a base layer; and asignal pad and a ground strip on the base layer. The ground strip isadjacent to the signal pad.

In example 11, the subject matter of example 10 can optionally includethe ground strip positioned above a horizontal portion of aninterconnect of a TL-LGA socket. The horizontal portion is coupled tothe signal pad on the base layer. The base layer is above a conductivelayer of a housing body of the TL-LGA socket. The interconnect is in thehousing body. The interconnect includes a vertical portion coupled to ahorizontal portion. The housing body has a top surface and a bottomsurface that is opposite from the top surface. The top surface is aconductive layer.

In example 12, the subject matter of any of examples 10-11 canoptionally include a width of the ground strip greater than a width ofthe horizontal portion.

In example 13, the subject matter of any of examples 10-12 canoptionally include a gap between the ground strip and the signal pad onthe base layer.

In example 14, the subject matter of any of examples 10-13 canoptionally include a ground pad on the base layer. The ground pad iscoupled to the ground strip.

In example 15, the subject matter of any of examples 10-14 canoptionally include the ground strip having a rectangular shape. Theground strip includes at least one of a rounded corner and aperpendicular corner.

In example 16, the subject matter of any of examples 10-15 canoptionally include the ground strip coupled to the ground pad in atleast one of a longitudinal axis and an orthogonal axis. The groundstrip is coupled to the ground pad in the orthogonal axis with a groundvia.

In example 17, the subject matter of any of examples 10-16 canoptionally include the horizontal portion of the interconnect of theTL-LGA socket is parallel to the ground strip on the base layer tocreate a microstrip.

In example 18, the subject matter of any of examples 10-17 canoptionally include the signal and ground pads on the base layer have areduced pad area.

In example 19, the subject matter of any of examples 10-18 canoptionally include a flooded ground plane on the base layer. The floodedground plane is coupled to at least one of a ground reference and theground pad. The flooded ground plane has a corresponding pad openingsurrounding the signal pad on the base layer. The corresponding padopening includes a gap between the signal pad and the corresponding padopening.

Example 20 is an assembly, comprising: a package substrate; anintegrated circuit die coupled to the package substrate. The packagesubstrate includes a base layer. The base layer has a signal pad and aground strip; and a TL-LGA socket coupled to the package substrate, the(TL-LGA) socket including: an interconnect in a housing body, theinterconnect includes a vertical portion and a horizontal portion. Thehousing body has a top surface and a bottom surface that is oppositefrom the top surface. The top surface is a conductive layer. The baselayer is above the conductive layer of the housing body of the TL-LGAsocket. The ground strip is above the horizontal portion of theinterconnect of the TL-LGA socket. The horizontal portion is coupled tothe signal pad on the base layer.

In example 21, the subject matter of example 20 can optionally include awidth of the ground strip greater than a width of the horizontalportion. The ground strip is adjacent to the signal pad. The horizontalportion of the interconnect is parallel to the ground strip on the baselayer to create a microstrip.

In example 22, the subject matter of any of examples 20-21 canoptionally include a gap between the ground strip and the signal pad.

In example 23, the subject matter of any of examples 20-22 canoptionally include the ground strip coupled to a ground pad on the baselayer. The ground strip has a rectangular shape. The ground stripincludes at least one of a rounded corner and a perpendicular corner.The ground strip is coupled to the ground pad in at least one of alongitudinal axis and an orthogonal axis. The ground strip is coupled tothe ground pad in the orthogonal axis with a ground via.

In example 24, the subject matter of any of examples 20-23 canoptionally include the signal and ground pads on the base layer have areduced pad area.

In example 25, the subject matter of any of examples 20-24 canoptionally include the base layer having a flooded ground plane, theflooded ground plane coupled to at least one of a ground reference andthe ground pad. The flooded ground plane has a corresponding pad openingsurrounding the signal pad on the base layer. The corresponding padopening includes a gap between the signal pad and the corresponding padopening.

In the foregoing specification, methods and apparatuses have beendescribed with reference to specific exemplary embodiments thereof. Itwill be evident that various modifications may be made thereto withoutdeparting from the broader spirit and scope. The specification anddrawings are, accordingly, to be regarded in an illustrative senserather than a restrictive sense.

What is claimed is:
 1. A socket assembly, comprising: a socket having aninterconnect in a housing body, the interconnect includes a verticalportion and a horizontal portion, wherein the housing body has a topsurface and a bottom surface that is opposite from the top surface,wherein the top surface is a conductive layer; and a package having abase layer, the base layer includes a signal pad and a ground strip,wherein the base layer is above the conductive layer of the housing bodyof the socket, wherein the ground strip is vertically over thehorizontal portion of the interconnect of the socket, and wherein thehorizontal portion is coupled to the signal pad on the base layer. 2.The socket assembly of claim 1, wherein a width of the ground strip isgreater than a width of the horizontal portion, and wherein the groundstrip is adjacent to the signal pad.
 3. The socket assembly of claim 1,further comprising a gap between the ground strip and the signal pad. 4.The socket assembly of claim 1, wherein the ground strip is coupled to aground pad on the base layer.
 5. The socket assembly of claim 1, whereinthe ground strip has a rectangular shape, and wherein the ground stripincludes at least one of a rounded corner and a perpendicular corner. 6.The socket assembly of claim 4, wherein the ground strip is coupled tothe ground pad in at least one of a longitudinal axis and an orthogonalaxis, and wherein the ground strip is coupled to the ground pad in theorthogonal axis with a ground via.
 7. The socket assembly of claim 1,wherein the horizontal portion of the interconnect is parallel to theground strip on the base layer to create a microstrip.
 8. The socketassembly of claim 4, wherein the signal and ground pads on the baselayer have a reduced pad area.
 9. The socket assembly of claim 4,wherein the base layer has a flooded ground plane, the flooded groundplane is coupled to at least one of a ground reference and the groundpad, wherein the flooded ground plane has a corresponding pad openingsurrounding the signal pad on the base layer, and wherein thecorresponding pad opening includes a gap between the signal pad and thecorresponding pad opening.
 10. A package substrate, comprising: a baselayer; and a signal pad and a ground strip on the base layer, whereinthe ground strip is adjacent to the signal pad, wherein the ground stripis positioned vertically over a horizontal portion of an interconnect ofa socket.
 11. The package substrate of claim 10, wherein the horizontalportion is coupled to the signal pad on the base layer, wherein the baselayer is above a conductive layer of a housing body of the socket,wherein the interconnect is in the housing body, wherein theinterconnect includes a vertical portion coupled to a horizontalportion, and wherein the housing body has a top surface and a bottomsurface that is opposite from the top surface, and wherein the topsurface is a conductive layer.
 12. The package substrate of claim 11,wherein a width of the ground strip is greater than a width of thehorizontal portion.
 13. The package substrate of claim 10, furthercomprising a gap between the ground strip and the signal pad on the baselayer.
 14. The package substrate of claim 10, further comprising aground pad on the base layer, wherein the ground pad is coupled to theground strip.
 15. The package substrate of claim 10, wherein the groundstrip has a rectangular shape, and wherein the ground strip includes atleast one of a rounded corner and a perpendicular corner.
 16. Thepackage substrate of claim 14, wherein the ground strip is coupled tothe ground pad in at least one of a longitudinal axis and an orthogonalaxis, and wherein the ground strip is coupled to the ground pad in theorthogonal axis with a ground via.
 17. The package substrate of claim11, wherein the horizontal portion of the interconnect of the socket isparallel to the ground strip on the base layer to create a microstrip.18. The package substrate of claim 14, wherein the signal and groundpads on the base layer have a reduced pad area.
 19. The packagesubstrate of claim 14, further comprising a flooded ground plane on thebase layer, wherein the flooded ground plane is coupled to at least oneof a ground reference and the ground pad, wherein the flooded groundplane has a corresponding pad opening surrounding the signal pad on thebase layer, and wherein the corresponding pad opening includes a gapbetween the signal pad and the corresponding pad opening.
 20. Anassembly, comprising: a package substrate; an integrated circuit diecoupled to the package substrate, wherein the package substrate includesa base layer, wherein the base layer has a signal pad and a groundstrip; and a socket coupled to the package substrate, the socketincluding: an interconnect in a housing body, the interconnect includesa vertical portion and a horizontal portion, wherein the housing bodyhas a top surface and a bottom surface that is opposite from the topsurface, wherein the top surface is a conductive layer, wherein the baselayer is above the conductive layer of the housing body of the socket,wherein the ground strip is vertically over the horizontal portion ofthe interconnect of the socket, and wherein the horizontal portion iscoupled to the signal pad on the base layer.
 21. The assembly of claim20, wherein a width of the ground strip is greater than a width of thehorizontal portion, and wherein the ground strip is adjacent to thesignal pad, and wherein the horizontal portion of the interconnect isparallel to the ground strip on the base layer to create a microstrip.22. The assembly of claim 20, further comprising a gap between theground strip and the signal pad.
 23. The assembly of claim 20, whereinthe ground strip is coupled to a ground pad on the base layer, andwherein the ground strip has a rectangular shape, wherein the groundstrip includes at least one of a rounded corner and a perpendicularcorner, wherein the ground strip is coupled to the ground pad in atleast one of a longitudinal axis and an orthogonal axis, and wherein theground strip is coupled to the ground pad in the orthogonal axis with aground via.
 24. The assembly of claim 23, wherein the signal and groundpads on the base layer have a reduced pad area.
 25. The assembly ofclaim 23, wherein the base layer has a flooded ground plane, the floodedground plane is coupled to at least one of a ground reference and theground pad, wherein the flooded ground plane has a corresponding padopening surrounding the signal pad on the base layer, and wherein thecorresponding pad opening includes a gap between the signal pad and thecorresponding pad opening.